Fix SSL regression introduced in 3.3.9

The wrapper introduced to handle SSL timeout errors in Python 2.7
incorrectly assumed that instances of SSLError would always have a
string as their first element. The safer approach is to check the
message attribute on the error.

Fixes SSL read timeouts in Python 2.7

The ssl module in Python 2.7 raises timeouts as ssl.SSLError instead of
socket.timeout. When these timeouts are encountered, the error will be
re-raised as socket.timeout so it is handled appropriately by the
connection.

The client section of MONITOR output varies for TCP connections, unix socket
connections and commands executed from Lua scripts. Account for each of these
cases by including an additional key `client_type` in the MONITOR output.
`client_type` will be one of ('tcp', 'unix', 'lua'). `client_address` and
`client_port` vary based on the `client_type`.

Fixes #1201

Prior versions of 3.3.x could potentially raise a raw socket.error
(or one of its subclasses) instead of a redis.exceptions.ConnectionError.

Fixes #1202

Fixes #1200

Fix an issue where socket.timeout errors could be handled by the wrong
exception handler in Python 2.7.

versions 3.3.1, 3.3.2 and 3.3.3 could potentially hide ConnectionErrors
on Python 2.7. This change accurately identifies errors by both
exception class and errno to determine whether a nonblocking socket can
be read

versions 3.3.1, 3.3.2 and 3.3.3 could potentially hide ConnectionErrors
on Python 2.7. This change accurately identifies errors by both
exception class and errno to determine whether a nonblocking socket can
be read